(1) Field of the Invention
This invention relates to a gas-liquid contacting apparatus. Said apparatus is utilized for deodorizing gas.
(2) Description of the Prior Art
Conventionally, as system deodorizing offensive odor gas or harmful gas, the washing-absorbing system is most popularly employed. In order to increase the absorption efficiency for specific components in a gas, it is important to contact gas with liquid effectively as much as possible and to facilitate the chemical decomposition of these specific components and diffusion thereof into liquid. There are many types of equipment performing the washing-absorbing system. however, popular deodorizing equipment is classified into the packed tower system (FIG. 8) and spray system (FIG. 10). Referring to FIG. 8 and FIG. 10, same numerals in the drawings shall indicate identical or corresponding parts.
A washing-absorbing equipment of the packed tower system 21 is an equipment to contact gas with liquid by feeding a liquid 23 to the surface of a packing 22 having large surface area and feeding a gas 24 in the counter current (reversely directed to the dropping direction, in principle). Conditions of the packing are large specific surface area and high void ratio, low resistance to gas flow, and low occurence of overflow or drift. Further conditions are high acid resistance, low specific gravity and high mechanical strength. Packings popularly used are of two types as illustrated in FIG. 9.
A spray tower 31 is used for humidifying, cooling and dust-collecting of gas while there can be used as a deodorizing equipment. The spray tower system easily causes drift, providing a bad influence to the deodorizing effect. In order to avoid such bad influence, the multi-stage spray system as illustrated in the drawing is used in many cases. A system illustrated in FIG. 10 is of two-stage type while three-stage type or five-stage type is actually applied for.
Since such a vertical type equipment is unable to use various types of chemicals by itself, three equipments are required to use three types of chemicals, for instance.
On the packed tower system, operation becomes impossible owing to the splash phenomenon of liquid if the flow rate of gas is too high while too small quantity of feeding liquid causes drift and too much quantity causes overflow. Chemicals containing solids or sediments can cause clogging where is required much maintenance to remove clogging and replace packings.